module yihuomen(in1,in2,out);
input wire[0:0] in1;
input wire[0:0] in2;
wire[0:0] a,b,c;
output wire[0:0] out;
yufeimen d1(.in1(in1),.in2(in2),.out(a));
yufeimen d2(.in1(in1),.in2(a),.out(b));
yufeimen d3(.in1(a),.in2(in2),.out(c));
yufeimen d4(.in1(b),.in2(c),.out(out));
endmodule